I am exactly halfway through my training regimen; 9 weeks down and nine to go. The first half is probably easiest; I've run 180 miles so far, and the next nine weeks calls for an increase to 250. On the other hand, I spent a lot of the early weeks getting back into the groove and building up a bit of stamina. So, I have a lot of work ahead of me, but I am better prepared to do it.
I'm starting to be more confident that I can beat my 1990 time of 4:23. To be honest, I like the idea of funning faster at age 52 than 30! I'll know better about that goal when I give my next monthly update.